Configured blast fragmentation warhead

ABSTRACT

A warhead for a guided missile or the like is provided with selectively operable multiple initiation devices, encased in a contoured fragmentation casing designed to optimize the initial available explosive energy to effect the most efficient transfer of energy into high velocity fragments. A shift of the fragment beam spray can be obtained by selective initiation of either end of the warhead or simultaneous initiation at both ends.

ilited States Eatent Moe Dec. 10, 197

[54] CONFIGURED BLAST FRAGMENTATION 3,136,251 6/1964 Witow 102/67 WARHEAD 3,447,463 6/1969 Lavine 4 l02/67 3,490,374 1/1970 Nooker i. 102/67 [75] Inventor: Richard G. Moe, China Lake, Calif. [73] Assignee: The United States of America as Primary Examiner Pendegrass represented b the secretary f the Attorney, Agent, or FirmR. S. Sciascia; Roy Miller; Navy, Washington, DC. Gerald Baker [22] Filed: Jan. 11, 1971 [57] ABSTRACT [21] Appl 105739 A warhead for a guided missile or the like is provided with selectively operable multiple initiation devices, 52 US. (:1. 102/67, IOZ/DIG. 2 encased in a contoured fragmentation casing designed [51] Int. Cl. F42!) 13/48 to Optimize the iniiial available explosive energy to [58] Field of Search... 102/64, 67 fect the most efficiem transfer of energy into high locity fragments. A shift of the fragment beam spray 5 References Cited can be obtained by selective initiation of either end of UNITED STATES PATENTS Steinmetz 102/64 the warhead or simultaneous initiation at both ends.

8 Claims, 9 Drawing Figures I A. WARHEAD INITIATION AT AFT END mamm 3.853.059

FBGJ.

C. WARHEAD INITIATION AT FORWARD END B. WARHEAD -|NIT|ATION AT BOTH ENDS (SIMULTANEOUSLY) INVENTOR.

RICHARD G. IVIOE BY ROY MILLER ATTOR NEY.

GERALD BAKER AGENT.

SHEET 2 OF 3 NM? MMP PATENIEU B53 1 M CONFIGURED BLAST FRAGMENTATION WARHEAD BACKGROUND OF THE INVENTION Prior fragmentation warheads have generally been initiated from a single, axially located, detonator. Such prior warheads were suitable, for example, in antipersonnel devices or the like where a pattern of widely scattered fragments was desirable. An air to ground missile warhead has been developed having a fragmentation pattern directed in accordance with a predetermined charge to metal ratio and designed for use against ground installations. One such warhead is described in assignees US. Pat. No. 3,498,224, issued Mar. 3, 1970. In air-to-air devices, however, it has been found that a more concentrated beam of fragments gives a much greater possibility of structural damage to the target.

According to the present invention, a configured blast fragmentation (CBF) warhead and a method is provided which causes the fragments to focus into an isotropic annular disk upon multipoint double end initiation or in a forward or aft conical disk when initiated on either end respectively. A shift of the fragment beam spray can be obtained by selective initiation of either end of the warhead, thus increasing the lethal interval of the warhead along the missile trajectory. In modern missiles, selective initiation may be accomplished with the aid of available missle intelligence through a simple logic switching network.

The'basic warhead initiation scheme is double ended,

, simultaneous, multipoint initiation. This causes the fragments to focus into an isotropic annular disk with the width of the disk being approximately equal to the original length of the warhead.

The successful use of this concept involves optimizing the energy content of the warhead/fragment systent. The basic philosophy is to optimize the initial available explosive energy (on an MV basis, for example) and effect the most efficient transfer of this energy into high velocity fragments.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a graphic illustration of the basic concept of the invention;

FIG. 2 is a perspective view partly in section showing a first embodiment of a warhead according to the invention;

FIG. 3a is a longitudinal cross sectional view of a sec- 0nd embodiment;

DETAILED DESCRIPTION OF THE INVENTION In FIG. 1 of the drawing it may be seen that when a warhead manufactured according to the present invention is initiated at the after end, a forwardly directed conical fragment pattern is achieved as shown at (A). A similar directional fragment pattern is directed aft when the warhead is initiated at the forward end as shown at (C). When the warhead is initiated at both ends simultaneously, the fragment beam tends to converge on a peripheral line that is at a radius from the warhead corresponding to the design radius for the particular configuration used. Many missiles, at present, have available information in the guidance circuitry which is sufficient to provide controls to selectively initiate detonation in an optimum mode based on some combination of missile and target attitude, proximity, etc.

The warhead 10, shown in FIG. 2, is encased in a shroud 12 and filled with a high explosive 14. Just inside of shroud 12 is a full length fragmentation layer 16 having a second fragment layer 18 fore and aft. A conventional safe and arm device 29 fills about half of the central cavity 20 and carries a booster 22 in most applications. Detonators 24 are placed in a plurality of locations spaced around the end plates 30, 30' and are connected to the booster 22 by means of detonation trains 26. The two end pieces 32, 32 are made integral with the shroud l2 and are configured to connect to other portions of a missile shroud by being provided with grooves or threads 28, 28 and necessary holes 33. Both fragment layers are scored on the inner surface in a grid pattern as shown at 19.

The warhead 100 shown in FIG. 3a is similar in most respects to the warhead 10 of FIG. 2. The fragment layer 116, however, is tapered from the center toward each end with a void space between the fragment layer 116 and shroud 112. Items in FIGS. 3a and 3b which are the same or similar to comparable items in FIG. 2 are designated by the same number increased by 100. Thus the shroud in FIG. 3a is 112, the'explosive material 114, etc., and the FIG. 4 device uses the same numbers in the 200 series.

The warhead 200 in the FIG. 4 version has the void space between the outer fragment layer 216 and shroud 212 filled with an inert material 204 which contributes to the warheads bullet resistance, shock resistance, heat resistance, etc.

FIG. 5 illustrates still another configuration of the fragment layers, similar to that in FIG. 4 but with the layers 316, 318 being straight.

FIGS. 6 and 7 illustrate how the booster or firing device is attached to the safe and arm device 29. The booster devices vary in configuration depending on the desired firing pattern. The booster shown in cross section in FIG. 8 will fire in a peripheral manner to ignite all of the detonation trains 26 (or 126, 226) simultaneously, thus causing multipoint double end initiation of the main explosive charge.

An optimum utilization of the CBF warhead concept should utilize a fragment size and shape which produces the maximum target response. The optimum convergent fragment beam would converge on a peripheral line that is at a radius from the warhead corresponding to the maximum catastrophic kill radius of the warhead design. The CBF designs tested thus far exhibit the largest catastrophic kill radius for a given weight limited warhead system.

A shift of the fragment beam spray (and a deemphasis of the fragment focusssing effect) can be obtained by selective initiation of either end of the warhead. This is useful in increasing the warheads lethal interval along the missile trajectory but requires the availability of certain missile intelligence and a simple logic switching and selectable initiation network.

Further, the CBF fragment lead angle can be altered by tapering the fragment wall to cause the fragments to converge on a peripheral line other than the focus point or line that would be produced by a cylindrical fragment wall. This also reduces the fragment velocity gradient and concentrates the fragmentation effects on a high velocity target.

Particular fragmentation warheads which optimize the initial total energy content of the fragments and concentrate this energy along a plane perpendicular to the warheads longitudinal axis have demonstrated superior lethality against aerial targets. The output of the Annular Blast Fragmentation (ABF) warhead mechanism is concentrated in a planar disk. The disk thickness is approximately the distance between planes perpendicular to the warhead longitudinal axis at each end bulkhead of the warhead. This localized energy on an aerial target results in a relatively large number of catastrophic structural kills as compared to other conventional warheads. The high velocity of the fragments alleviates the fuzing equation compromise that is required over a wide range of air target encounter conditions. Future application to surface targets is likely.

The ABF warhead configuration that is considered most promising is a cylindrical warhead utilizing double end, simultaneous initiation of multipoint boosters. The multi-walled, tapered cylindrical mild steel fragmenting case utilizes an inner surface grid system which controls the fragment size and shape. This fragment size and shape efficiently couples with the aerial targets, within the threat spectrum, to produce a high percentage of catastrophic structural kills. The explosive material is selected on a maximum energy basis with consideration given to bullet impact and open flame cook-off sensitivity.

What is claimed is:

1. A substantially cylindrical warhead having a fragmentation casing;

detonation initiation means centrally located in said warhead a plurality of detonation boosters spaced around each end of said warhead; and detonation transfer means connecting said intiation menas and said booster means;

whereby the warhead may be selectively detonated at a plurality of points at either end or both ends or detonated centrally.

2. A warhead according to claim 1 wherein said casing comprises a plurality of fragmentation layers.

3. A warhead according to claim 2 wherein said fragmentation layers taper from a maximum central diameter to a minimum diameter at the ends leaving a frustoconical torroidal space at each end between the outermost of said layers and said shroud.

4. A warhead according to claim 3 wherein said space is filled with an inert material.

5. A warhead according to claim 3 wherein said space is filled with an inert solid material.

6. A warhead according to claim 2 wherein said lay ers include a full length outer layer and one or more shorter inner layers.

7. A warhead according to claim 5 wherein said layers consist of one full length outer layer and one shorter, centrally located inner layer.

8. A warhead according to claim 5 wherein said layers consist of one full length outer layer and a shorter inner layer located at each end. 

1. A substantially cylindrical warhead having a fragmentation casing; detonation initiation means centrally located in said warhead a plurality of detonation boosters spaced around each end of said warhead; and detonation transfer means connecting said intiation menas and said booster means; whereby the warhead may be selectively detonated at a plurality of points at either end or both ends or detonated centrally.
 2. A warhead according to claim 1 wherein said casing comprises a plurality of fragmentation layers.
 3. A warhead according to claim 2 wherein said fragmentation layers taper from a maximum central diameter to a minimum diameter at the ends leaving a frusto-conical torroidal space at each end between the outermost of said layers and said shroud.
 4. A warhead according to claim 3 wherein said space is filled with an inert material.
 5. A warhead according to claim 3 wherein said space is filled with an inert solid material.
 6. A warhead according to claim 2 wherein said layers include a full length outer layer and one or more shorter inner layers.
 7. A warhead according to claim 5 wherein said layers consist of one full length outer layer and one shorter, centrally located inner layer.
 8. A warhead according to claim 5 wherein said layers consist of one full length outer layer and a shorter inner layer located at each end. 